Need Open Source Shopping Cart Software?

I'm looking to purchase ecommerce software that I can use to create shopping site for clients. It needs to be secure, reliable, easy to use and update.Does anyone have any recommendation's on good e-commerce software? All genuine advice welcomed. 

Check Magento. It is one of the best and it is free :)

There are several out there. Magento is one of the best I think.
If you were to use Drupal as your content management system you'd be looking at Ubercart.

I prefer zeuscart which is the best open source shopping cart software. They provide good support and highly secure services.

Have a look at Zend cart and Joomla with the virtuemart plugin
I have setup both for freinds or you can download the compleat package from virtuemart, I have setup both for freinds

Joomla/virtue mart has some advantages as other plugins or extensions can be added later Virtuemart has a csv upload as well but it can take some time to setup if you need to creat new templates
also their is oscommerce.

They are Opensource aslo have a look on sourceforge for ecomerce scripts  Or better still creat a store yourself from scratch

Zeuscart is the best open source e-commerce solutions ever, try it!

ZenCart is a pretty good one, it has a self install script in Fantastico.

Yeah, I use Zencart too

some benefits as other plugins or additions can be supplemented subsequent Virtuemart has a csv upload as well but it can take some time to setup if you require to creat new templates